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A benign esophageal leiomyoma with abnormally increased fluorine-18-fluorodeoxyglucose uptake on positron emission tomography (PET) was resected thoracoscopically. The tumor, of which the maximum standardized uptake value of the lesion was 4.7, was well defined and 38 mm in diameter. Neither mitotic activity nor degeneration was found histologically; and immunoreactivity for CD34, CD117, MIB-1, and glucose transporter-1 was negative immunohistochemically. A diagnosis of gastrointestinal stromal tumor was ruled out by an oncogenic kinase gene mutation study. This case cautions against PET-dependent evaluation for malignant potential of esophageal submucosal tumors.  相似文献   
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Some investigators have suggested that preoperative chemotherapy for hepatic colorectal metastases may cause hepatic injury and increase perioperative morbidity and mortality. The objective of the current study was to examine whether treatment with preoperative chemotherapy was associated with hepatic injury of the nontumorous liver and whether such injury, if present, was associated with increased morbidity or mortality after hepatic resection. Two-hundred and twelve eligible patients who underwent hepatic resection for colorectal liver metastases between January 1999 and December 2005 were identified. Data on demographics, clinicopathologic characteristics, and preoperative chemotherapy details were collected and analyzed. The majority of patients received preoperative chemotherapy (n = 153; 72.2%). Chemotherapy consisted of fluoropyrimidine-based regimens: 5-FU monotherapy, 31.6%; irinotecan, 25.9%; and oxaliplatin, 14.6%. Among those patients who received chemotherapy, the type of chemotherapy regimen predicted distinct patterns of liver injury. Oxaliplatin was associated with increased likelihood of grade 3 sinusoidal dilatation (p = 0.017). Steatosis >30% was associated with irinotecan (27.3%) compared with no chemotherapy, 5-FU monotherapy, and oxaliplatin (all p < 0.05). Irinotecan also was associated with steatohepatitis, as two of the three patients with steatohepatitis had received irinotecan preoperatively. Overall, the perioperative complication rate was similar between the no-chemotherapy group (30.5%) and the chemotherapy group (35.3%) (p = 0.79). Preoperative chemotherapy was also not associated with 60-day mortality. In patients with hepatic colorectal metastases, preoperative chemotherapy is associated with hepatic injury in about 20 to 30% of patients. Furthermore, the type of hepatic injury after preoperative chemotherapy was regimen-specific. Presented at the American Hepato-Pancreato-Biliary Association 2006 Annual Meeting, March 11, Miami, Florida.  相似文献   
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The objective of this systematic review was to evaluate the impact of pharmacist delivered community-based services to optimise the use of medications for mental illness. Twenty-two controlled (randomised and non-randomised) studies of pharmacists' interventions in community and residential aged care settings identified in international scientific literature were included for review. Papers were assessed for study design, service recipient, country of origin, intervention type, number of participating pharmacists, methodological quality and outcome measurement. Three studies showed that pharmacists' medication counselling and treatment monitoring can improve adherence to antidepressant medications among those commencing treatment when calculated using an intention-to-treat analysis. Four trials demonstrated that pharmacist conducted medication reviews may reduce the number of potentially inappropriate medications prescribed to those at high risk of medication misadventure. The results of this review provide some evidence that pharmacists can contribute to optimising the use of medications for mental illness in the community setting. However, more well designed studies are needed to assess the impact of pharmacists as members of community mental health teams and as providers of comprehensive medicines information to people with schizophrenia and bipolar disorder  相似文献   
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Statutory reimbursement agencies as well as private insurers throughout member states of the Organization for Economic Cooperation and Development (OECD) reimburse the cost of medicines on the basis of criteria that include robust clinical evidence, budget impact analysis, and incremental cost effectiveness. The Centers for Medicare and Medicaid Services (CMS) in the US are no exception to this rule and are, in principle, seeking to maximize benefit for their Medicare enrollees, whilst ensuring reasonable drug outlays for the small number of drugs that they reimburse. This paper provides a retrospective analysis of the way two functionally equivalent drugs are treated for reimbursement purposes by the CMS; the period under consideration was 2001–3. The two drugs, epoetin-α and darbepoetin-α, are used for the treatment of anemia in renal failure and in patients receiving chemotherapy. By reviewing the publicly available pharmacological and clinical data of epoetin-α and darbepoetin-α, the paper confirms the two drugs’ functional equivalence, despite their structural differences. The implications of dose conversion ratios and costs to Medicare are subsequently explored. It is argued that the issue of dose equivalence between epoetin-α and darbepoetin-α has significant implications for patients, practitioners, and payors. A payor’s perspective is adopted in this respect, whereby clinical evidence and pricing data are used simultaneously. Based on the clinical evidence, a dose conversion ratio for epoetin-α:darbepoetin-α is established, which achieves a comparable clinical effect for the two drugs and this is set to be <254IU:1μg. The incremental costs to Medicare are calculated subsequently. The Average Wholesale Price and the Outpatient Prospective Payment System rule that Medicare uses to reimburse providers are used and suggest that treatment of cancer patients with chemotherapy-related anemia with epoetin-α would save Medicare an estimated $US600 million each year. Patients would also benefit significantly in terms of lower co-payments for epoetin-α. The evidence is supportive of the decision made by the CMS to reimburse the two drugs at the rate reflecting the achievement of comparable clinical effects and therefore reducing the pass-through payments for darbepoetin-α to zero for the 2002–3 fiscal year.  相似文献   
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Objective: To study the diagnostic value of T2^*-weighted first-pass perfusion imaging in breast tumors. Methods: We analyzed the magnetic resonance imaging (MRI) information along with the pathological and immunohistochemistry results. Magnetic resonance imaging was performed in 28 patients with breast tumor. The time to signal intensity curves were generated according to the T2^*-weighted first-pass perfusion imaging. The curve's maximal signal intensity drop rate and maximal signal intensity decrease time were analyzed and compared with the pathological diagnoses after surgery. Results: Malignant breast lesions showed higher maximal signal intensity drop rate (44.69% ± 17.07 vs. 17.22% ±7.49, P 〈 0.001) than benign lesions, but there was no significant difference of maximal signal decrease time between those two lesions (23.94 s ± 4.92 vs. 20.02 s ± 6.83, P 〉 0.05). Conclusion: The T2^*-weighted first-pass perfusion imaging has enough sensitivity and specificity in breast tumor diagnosis.  相似文献   
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Fate of micelles and quantum dots in cells.   总被引:2,自引:0,他引:2  
Micelles and quantum dots have been used as experimental drug delivery systems and imaging tools both in vitro and in vivo. Investigations of their fate at the subcellular level require different surface-core modifications. Among the most common modifications are those with fluorescent probes, dense-core metals or radionucleids. Cellular fate of several fluorescent probes incorporated into poly(caprolactone)-b-copolymer micelles (PCL-b-PEO) was followed by confocal microscopy, and colloidal gold incorporated in poly 4-vinyl pyridine-PEO micelles were developed to explore micelle fate by electron microscopy. More recently, we have examined quantum dots (QDs) as the next-generation-labels for cells and nanoparticulate drug carriers amenable both to confocal and electron microscopic analyses. Effects of QDs at the cellular and subcellular levels and their integrity were studied. Results from different studies suggest that size, charge and surface manipulations of QDs may play a role in their subcellular distribution. Examples of pharmacological agents incorporated into block copolymer micelles, administered or attached to QD surfaces show how the final biological outcome (e.g. cell death, proliferation or differentiation) depends on physical properties of these nanoparticles.  相似文献   
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